By Kevin Murphy For the Times MADISON - A Green County man's five-year effort to reverse a homicide conviction for killing his infant son apparently ended this month as the Wisconsin Supreme Court denied a request to hear the case. Jurors found Casey J. Shelton, 38, guilty of first-degree reckless homicide in January 2009, and eight months later Circuit Judge James Beer sentenced Shelton to 40 years in prison. Since then, Shelton's attorneys have in two unsuccessful attempts contested many aspects of the trial at which he was found guilty of causing the death of 2-month-old Christopher Shelton on Feb. 28, 2007.